Calgary - July 20, 2011 - CNOOC Limited, China’s largest producer of offshore crude oil and natural gas and one of the largest independent oil and gas exploration and production companies in the world, announced that CNOOC Luxembourg s.à r.l, an indirect wholly-owned subsidiary of the CNOOC Limited, had entered into an arrangement agreement to acquire OPTI Canada Inc., a Calgary-based company focused on developing major oil sands projects in Canada.

The aggregate value of the consideration of the transaction is approximately US$2.1 billion, which includes aggregate cash consideration of US$1.25 billion payable to the holders of the OPTI shares and the Second Lien Noteholders and the assumption of US$825 million First Lien Notes. The transaction will be effected by way of a plan of arrangement through concurrent proceedings under the Companies’ Creditors Arrangement Act (Canada) and the Canada Business Corporations Act.

Gowlings is advising CNOOC Limited in this transaction with a team led by Calgary partner and well respected M&A lawyer, David Lefebvre. “Increasingly, Asian companies are making major acquisitions and investments in Canada, and Gowlings is well positioned to serve its clients in this regard, especially with its strengths in public policy, government and foreign affairs,” said Mr. Lefebvre. “Our firm recognizes the growing global importance of China and Asia, and in line with this, Gowlings has already announced plans to open an office in Beijing later this year.”

The proposed transaction must be approved by the Second Lien Noteholders at a special meeting that is expected to be held in September 2011. The proposed transaction is also subject to certain terms and conditions, including, among other things, applicable government and regulatory approvals by the relevant authorities in Canada and the People’s Republic of China, and Canadian court approval. The transaction is expected to be completed in the fourth quarter of 2011.

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